Two number when divided by 17, leaves remainder 13 and 11 respectively. If the sum of those two numbers is divided by 17, the remainder will be ?

Answer: Option C

Dividend = divisor × quotient + remainder
$$\begin{array}{rl}& \text{First number }\\ & \Rightarrow \left(17\times \text{n}\right)+13\\ & \text{Let n = 1}\\ & \Rightarrow (17\times 1)+13\\ & \Rightarrow 30\\ & \text{second number }\\ & \Rightarrow \left(17\times \text{n}\right)+11\\ & \Rightarrow (17\times 1)+11\\ & \Rightarrow 28\\ & \text{According to question}\\ & =\frac{30+28}{17}\\ & =\frac{58}{17}\\ & \Rightarrow \text{remainder = 7}\end{array}$$

Alternate :
Divisor = 1^st remainder + 2^nd remainder - 3^rd remainder
$$\begin{array}{rl}& 17=13+11-\text{3rd remainder}\\ & \text{3rd remainder}=24-17=7\end{array}$$